JZ30

every once in a while my car just shuts off on me. no warning. no nothing. it's usually when i'm coming to a stop. i've changed the fuel filter, air filter, and mass air flow sensor and that has'nt helped. any ideas???

GOLDSc300

Could it be caused by dirty fuel injectors?

JZ30

i did put a bottle of fuel injector cleaner in the last 3 times i filled up with gas........but, does that stuff really work? or is it just a scam? the first time i used a bottle of that stuff, i bought the most expensive formula availiable (still only $10) cuz i figured, you get what you pay for. but then i used the cheaper stuff (about $5) the last two times i filled up. still haven't noticed a difference.

risc4

Sounds like an engine stall-out but could it be a battery kill? I had a similar situation but it was due to a loose battery cable.

THE_CEO

the fuel injection cleaner works....infact they recommend that you use it once every 4000 miles...

CEO

link13

I had the same problem with my Corolla GTS a few years ago except that the shutoff would also happen at speed. I could always restart it right way, but it was annoying. My Dad checked the Main EFI relay and noticed that it was warm to the touch, but the other relays weren't. He replaced the EFI relay and the problem was solved.

O. L. T.

iTrader: (17)

I think you immediately answered your own question right off the bat. "when i come to a stop" means you are lowering your rpm's and fuel pressure. by a lack of fuel pressure your engine drops idle and dies. A simple search of the site would reveal this is a fairly common problem. you need to replace your fuel pump. good luck.

JZ30

i actually did a lot of searching before i posted this, thats why so far i.......................

checked the connection of battery terminals

replaced the air filter

replaced the fuel filter

used fuel injector cleaner (last 3 times i filled up.)

serviced the transmission

replaced the mass air flow sensor

today i'm changing the plugs,cap, and rotor

i've taken the car to the dealer and another mechanic already and niether of them could find the problem.
they checked the fuel pressure and said it was fine. when the guy at the mechanics shop drove it, it did not hesitate or shut off on him....so he said he could not fix it. when the guy at the dealer drove it he said it did hesitate on him a couple of times, but when they went did the diagnosis, nothing came up.

is there a possibility if the fuel pump is bad that it only works decent sometimes and less than decent other times?

SRQ400

Yes, mine has but only once during cooler weather when the A/C wasn’t on. Check the GS forum you’ll see a lot of info leading to no answer other than a possible ECU malfunction brought to you by Toyota/Lexus!
I wasn’t driving it at the time but it scared the livin’ poop out of her.
It seems to me that there is an inherent problem with the ECU that can’t compensate for temperature changes within voltage parameters. Many of the quick fixes seem to deal with increasing the voltage demand. But there seems to be no real one answer to this problem.

O. L. T.

iTrader: (17)

I see you've searched, and i see you've replaced, but i dont see the word "fuel pump" in there anywhere.
It could be anything, but experience tells us that the fuel pump is usually the problem. and yes, it can operate anytime it wants if a component is going bad, it isnt just a motor, it's a wad of electrical parts.

Either way i hope it turns up soon before you get over your head in expenses. Good luck.

JZ30

i guess the fuel pump will be next.

should'nt the dealer be able to find out whats wrong in the first place? i cant believe i'm still not sure what the problem is AFTER taking it to the dealer AND another mechanic for a second opinion.

thank you for all of your imput so far.

reamemiya

iTrader: (1)

i to think it's due to the fuel which causes bad idling that would cause the stall/stop. as a previous owner of an FD many people encountered this problem on the rx7.

reamemiya

iTrader: (1)

dealership are iffy... i woudln't trust them much...maybe look for a lexus/toyota specialist. plus dealerships charge a lot of fee's you'll end up paying twice as much. this isn't meant for all dealers but most. and most of the mechanics that work on the car are ametuers anyways...

JZ30

believe it or not ........the mechanic is a toyota/lexus specialist.

SRK

My experience working on other brands is that a quick stall, not preceded by rough running is usually the result of a relay tripping. If the engine restarts quickly and smoothly, that tends to confirm the relay trip. Something is shutting down the entire engine, not just one or two cylinders. That means that the problem is not spark plugs, or plug wires, or injectors. It may be something causing a complete loss of fuel or ignition, but not the individual cylinder components.
Fuel pump relay, main relay (where ever that is on these cars), or perhaps a large air leak downstream of the mass meter, if you are convinced that this occurs only when stopping (engine movement twisting the intake hose).
Good luck with it - these kinds of problems can be frustrating.